RESUMO
Recovery of enzymes such as FPase (filter paperase) or exoglucanase from fermented substrate is a sustainable approach in enzyme production; however, there is a scarcity of optimization studies in this field. The present study was aimed to standardize number of parameters (selection of solvent, solvent volume, soaking time, leaching conditions and number of washes) to extract maximum amount of FPase from fermented rice husk by Aspergillus protuberus. Novel Aspergillus protuberus was first report from our lab on cellulases production in solid state fermentation (SSF). Among the tested solvents, citrate phosphate buffer (0.02 M, pH 5.0) proved best solvent for maximum recovery of FPase. Consequent experimental parameters were further optimized with citrate phosphate buffer. Two washes with citrate phosphate buffer each by shaking (60 min) in a ratio of 1 g of rice husk: 5 ml of citrate phosphate buffer together attained higher recovery efficiency (88 %) of FPase from the fermented rice husk.
RESUMO
Environmental problems are caused by the disposal of agrowastes in developing countries. It is imperative to convert such wastes into useful products, which require enzymes such as ß-glucosidase. ß-Glucosidase has variety of applications in biotechnology including food, textile, detergents, pulp and paper, pharmaceutical and biofuel industries. ß-Glucosidase production was performed using the locally isolated Aspergillus protuberus using best growth circumstances on rice husk in solid-state fermentation (SSF). Leaching of ß-glucosidase from fermented rice husk with number of solvents to evaluate their extraction efficacy. Among the different solvents examined, acetate buffer (0.02 M, pH 5.0) proved to be the best solvent. The subsequent parameters were optimized with acetate buffer. Two washes with acetate buffer each by shaking (30 min) in a ratio of 1 g of rice husk: 5 ml of acetate buffer together attained maximum recovery of ß-glucosidase with 41.95 U/g of rice husk.
Assuntos
Aspergillus , Oryza , beta-Glucosidase , Fermentação , Solventes , AcetatosRESUMO
Background: After mass drug administration to eliminate human lymphatic filariasis, there is a need for surveillance to detect the measurable endpoint of the program. Methods: An immunodominant seroreactive clone, WbL1, was identified through immunoscreening of a Wuchereria bancrofti L3 complementary DNA expression library. Recombinant WbL1 (rWbL1) was analysed with sera from W. bancrofti patients. Diagnostic evaluation was carried out by developing an enzyme-linked immunosorbent assay (ELISA) to detect the filarial-specific antibodies in various categories of filarial sera samples against recombinant WbL1 (rWbL1) protein. Results: Performance parameters of the test in terms of immunoglobulin G (IgG) and IgG4 detection displayed significant sensitivity and specificity values up to 77% and 100%, respectively. Our results showed filarial antibodies against rWbL1 to be highly reactive with microfilaremic and clinical filarial sera samples compared with the endemic and non-endemic control sera samples. Reasonably satisfactory performance of the test was also confirmed from the multicentric evaluation of an anti-WbL1 IgG4 detection ELISA. This test was found to be minimally reactive with other nematode parasites and protozoan infections. Conclusions: The anti-WbL1 IgG4 detection test can be considered as a field test for initial screening and epidemiological monitoring of filarial infections in filariasis-endemic areas.